1. Field of the Invention
This invention relates generally to life-saving appliances, employing inflatable tubes as life preservers, and more particularly, to such appliances that are compact in size and can easily be thrown to a person in distress to assist in the rescue of such person.
2. Description of the Prior Art
Life-saving appliances employing inflatable tubes and individual pressurized containers therefor are well-known. Generally, in order to facilitate the handling and storage of such appliances prior to their usage, the tubes are deflated and the pressurized containers are retained in their unactuated condition by a valve-locking mechanism that may assume several forms, including the form of a spring-operated mechanical timing mechanism, a water-soluble pellet, or a water-soluble strap. A representative mechanical-timing mechanism is disclosed in U.S. Pat. No. 2,857,078, granted to H. Wolpert; a representative water-soluble capsule is disclosed in U.S. Pat. No. 3,350,730, granted to Kubit, et al.; and a representative water-soluble strap is disclosed in U.S. Pat. No. 3,682,354, granted to Witte. Each of these representative prior art, life-saving appliances suffers from one or more of the deficiencies noted hereinafter.
To illustrate, the several components of the mechanical-timing mechanism disclosed by Wolpert are relatively expensive to manufacture and properly assemble with the extreme degree of reliability necessary for successful operation of life-saving appliances. Also, by virtue of the manner in which the timing mechanism is interposed between the deflated tubular life preserver and the capsule of compressed gas, the life-saving appliance is bulky and cannot be thrown an appreciable distance. The water-soluble capsules employed by Kubit et al. exhibit a tendency to crumble or disintegrate and thus prematurely release the locking mechanism for the valve operator of the pressurized fluid container. Witte thus suggests replacing the water-soluble capsule with a liquid deteriorative strap that more effectively retains the locking mechanism for a pressurized fluid container in its normally unactuated condition. In both instances, the life-saving appliance is housed within a casing that has holes formed therein so that the capsule, or strap, can be completely wetted when the housing is immersed in water. However, in order to allow the inflatable tube to expand, the person in distress in the water must open such housing to allow the inflatable tube to expand, a seemingly simple task under normal circumstances, but one that may create problems when panic overwhelms the distressed user of these appliances.